As the applicant has previously noted in pending applications U.S. Pat. No. 6,476,863 and U.S. Pat. No. 6,459,495 there is a general need for a print media scanning system that allows for high volumes of computer data to be stored on a simple print media, such as a card while simultaneously tolerating a high degree of corruption when read by a scanning device. For example, the form of distribution can suffer a number of data corruption errors when the surface is scanned by a scanning device. The errors can include:    1. Dead pixel errors which are a result of reading the surface of the card with a linear CCD having a faulty pixel reader for a line thereby producing the same value for all points on the line.    2. Preferably, the system adopted can tolerate errors wherein text is written by the owner of the card on the surface. Such errors are ideally tolerated by any scanning system scanning the card.    3. Various data errors on the surface of the card may arise and any scuffs or blotches should be tolerated by any system determining the information stored on the surface of the card.    4. A certain degree of “play” exists in the insertion of the card into a card reader. This play can comprise a degree of rotation of the card when read by a card reader.    5. Further, the card reader is assumed to be driven past a linear image sensor such as a CCD by means of an electric motor. The electric motor may experience a degree of fluctuation which will result in fluctuations in the rate of transmission of the data across the surface of the CCD. These motor fluctuation errors should also be tolerated by the data encoding method on the surface of the card.    6. The scanner of the surface of the card may experience various device fluctuations such that the intensity of individual pixels may vary. Reader intensity variations should also be accounted for in any system or method implemented in the data contained on the surface of the card.
Ideally, any scanning system should be able to maintain its accuracy in the presence of errors due to the above factors.
In applications U.S. Pat. No. 6,476,863 and U.S. Pat. No. 6,459,495, the applicant disclosed a method and apparatus for printing data in an encoded fault tolerant form on the back of a photograph preferably using black ink on a white background. The data represented the photograph in a digital image file format and/or data comprising a computer program script which could be run to recreate the image or to apply some effect to the image. A programming language called a VARK script was invented for this purpose which was designed to be portable and device independent.